Wondering if anyone else experiences this 'flip'

[InvisibleDeath]

I don't always see this happen, but when it does it is usually after running SH4 for several hours.

In this particular case I inserted a spy in Japan. That mission ran for days and the insertion required waiting to do it in the stealth of darkness.

The insertion was near the bay that Tokyo is in so I backed out of there, went past the small islands across from my bay, and went into the next bay to draw attention away from my drop.

I took on a juicy merchant, nailed it with a torpedo, and finished it with my guns. While we pursued him we got a hit of a second merchant, this is definitely happy days. After dropping the merchant I went in pursuit of the second target with what looked like a convoy getting added to my collection of targets coming in the bay. I followed my merchant and got the sub in position. We had to sit in position much for several hours.

Now comes the flip. I put my scope on the target and went through the process of setting up my torpedoes. My lock indicator was red at the time however it was a steep angle to the west so I wasn't concerned. However at the proper angle it still read red and if I switched to aft torpedoes it was yellow. This is in spite of the fact that the target was in front of me not behind me!!! In a test I found that if I save my game while the ship is still in sight, exit to Windows, then restart the game my torpedoes operate correctly.